Apparatus for servicing brushes on the traction motors of diesel-electric locomotives



T. SlMPKlN VIC Apri124, 195e 2,742,803 AP ATUS FOR SER ING BRUSHES ON THE TRACTION OTORS O I L-ELECTRIC LOCOMOTIVES i1 OCT.. 24, 1952 United States Patent A-RPARATUS FOR S'ERVICING BRUSHES 0N THE r[RACTION MOTORS 0F DIESEL-'ELECTRIC L0- COMOTIVES Thomas Simpkin, Hannibal, Mo.

Application October 24, 1952, Serial No. 316,684

3 Claims. (Cl. 81'3) This invention relates to electric motors, and more particularly, to apparatus for servicing 'the commutator brushes inl the traction motors of diesel-'electric locomotives.

To Athose charged with the maintenance of dieselelectric locomotives, the inspectionr and replacement of the brushes in the traction motors has beeny a troublesome. and time-consuming task. As some indication of thev scope of; :the job, it ispointed out that each unit of 'the' locomotive generally has four traction motors, and that each-motor generally has -four brush holders, each of which contains several brushes, and that `all of the brushes are serviced when the engine is given the usual overhaul at the end ofA a run.. Il-he brushes are held in the, brushholders by stift springs, which engage the outer ends thereof so that they` are continuously biased against the commutator. When it is desired to service a brush, its associated spring must be lifted against bias and while held inthe stressed condition, the brush is lifted from the holder.

It, is accordingly an object of this invention to provide apparatus for more conveniently lifting brush springs and for maintaining a spring lifted while freeing the workers hands for manipulation of the brushes. Among 'the Several other objects of the invention is the provision of apparatus of this class which may be fixedl in position to hold a brush spring in elevated conditiony without otlering interference to withdrawal of a brush; and Ithe provision in apparatus of the type/described of means for aligningthe apparatus in position clear of the path of withdrawal of a brush.

Toythe attainment of these objectives, I provide ap- I paiatus.l comprising an elongate handle, which may be readily inserted through the. usual brush-access opening int the. housing to pry up a brush spring.I A spring lifter is carried. at one endv of theV handle for cooperation with av brush spring,v and at or adjacent the other end of the handle, there is means for seating the handle upon the housing at the edge of the access opening, whereby the springV may be4 maintained in elevated condition. Moreover, the spring lifter is supported in olset relationship from the handle, as by spaced legs in order to clear the path 4ol withdrawaly of the released brush, and in a preferred form of the invention, the spring lifter is provided with gu-ides, such as lingers which straddle the spring, disposedu to align the supporting legs of the spring lifter upon opposite sides of the brush tov be released.

Other features of theV invention will bein part apparent from. and irrpart pointed out in the following detail. description, taken in connection with the accompanying drawings, in which:

Fig. 1 is an end View of a traction motor as it appears in a diesel-electric locomotive, pants being broken away to illustrate the brush-servicing apparatus of this invention; and, f

Fig. 2 is an enlarged oblique view of one of the brush holders of Fig. l illustrating the apparatus in greater detail.

It is to be understood that the conventional dieselelectric locomotive includes a plurality of direct current motors mounted in the trucks of the locomotive to turn `the drive wheels. Generally, each unit of the locomotive has four traction motors. A diesel-driven generator supplies power to the motors, and the motor windings are connected in variousways under control from the engineers cab to provide for various driving and braking conditions. Each motor housing, which is of the enclosed type, is secured to the frame of the truck, and the motor shaft is geared to one or more drive wheels. The motors, of course, have Xed field windings and rotating armature windings, the latter being suppliedv through a commutator and brushes. These details are not described further nor lillustrated, because they are known in the art and serve merely as background for the subject matter to be disclosed more particularly.

Referring now to the drawings, Fig. l is a diagrammatic view of the commu'tator end of a traction motor, certain details not pertinent herein. being omitted for purposes of clarity. A motor housing -is shown at 1 to extend over and enclose a commutator 3, and the housing is provided with removable cover members, one of which is shown at 5. During servicing, the covers 5 are removed Vto afford access to thecommutator 3 through suitable openings, one of which is shown at 7. Within this housing `there are mounted certain brush holders 9 and l0, two of which are shown in Fig. l, but it is to be understood that there are two additional brush holders (generally opposite thoseshown) to which access may be had by removal of the cover member 5.

The brush holders each comprise a frame having a back portion 1l, side arms 13, and a front portion 15, in which the brushes are received. Insulator supports 17 on the back portion support the brush holder from the housing 1 so that the front brush-receiving portion 15 is cantilevered over rthe commutator 3 in spaced relationship. Arranged across the commutator are three brush receptacles 19 in the form of slots extending normal to the surface of the commutator for reception of brushes 21.

rPhe brush holders also include spring elements for applying pressure on the brushes in order to maintain proper contact with `the commutator without excessive wear. Each brush receptacle 19 has an associated spring 25 coiled about and secured to a transverse rod 27. This rod `is fastened in the side arms13 of the frame to ei:- tend generally Abetween the fore and aft frame parts l5 'and 11, respectively. Plates 29 secured to `the outer ends of these springs engage the `back portions of the brushes where they project 4from their receptacles. These plates 29 are conductively connected to the frame by flexible straps 31, The brushes themselves may also have pigtails (not shown) imbedded therein for connection to the frame, so as to further minimize losses at the brushes in a manner known in the art. It will be understood that the frame of the brush holder is formed of conductive material and has connections (not shown) which extend through the housing 1.

When it is, necessary to inspect or replace vone of the brushes', the free end 29 of Ithe associated spring is lifted (Fig. l) so that the brush is then free to be withdrawn out of its receptacle,- which is recessed at 3l) to permit entry of the fingers. Heretofore the process has been entirely manual in that the spring was pushed back and held by one hand while the other hand was employed to remove the brush. It will be apparent that the hand which holds the spring must be disposed, perhaps awkwardly, soas not to interfere with manipulation of the brush. i

This invention contemplates the provision of apparatus, generally `designated 33, to facilitate lifting of a "ice 'handle formed as by a metal bar 35 with side pieces 37 of wood secured thereto. At its forward end, the bar 35 projects beyond the wooden handle portions 37 and carries an open head generally in the outline of the head of a y swatter. This head may be formed from rod stock with end portions 39 secured to the bar 35 as by welding, and with spaced legs 41 projecting forwardly to a bridging spring lifter portion 43, Centrally disposed upon the forward bridging portion l'i3 there is a spring lifter bracket 45 which is notched to provide fingers 47 which straddle the end 29 of the spring elcment. This bracket serves as a guide element cooperable with the spring element to align the legs 41 of the head upon opposite sides of the proper brush.

In operation, the elongate handle permits two-handed manipulation of the apparatus somewhat in the manner of a shovel to pry up one of the springs. The handle also has an additional purpose. As indicated at 49, there is a notch disposed remote from the spring lifter so as to seat upon the edge 51 defining the brush-access opening 7 in the housing 1. Hence, after the appropriate spring has been lifted, the handle is merely seated upon the housing to retain the brush spring in elevated condition. The workman may then readily enter his fingers through the open head as indicated by dotted lines in Fig. 2 for access to the appropriate brush, and the brush may be lifted through the head opening, the legs 41 of which are so spaced apart as to permit passage of `the brush therethrough.

Although this arrangement is satisfactory for the brush holder 9, in practice the access opening is not symmetrically dsposed relative to the two brush holders. Hence when the other brush holder 10 is to be serviced, the notch 49 is not in proper relationship with respect to the edge 53 of the housing, but in this instance the end of the handle is notched as indicated at 55 to seat thereon. It will be understood the length of the handle is properly correlated with the access opening, this being possible because diesel-electric locomotives are somewhat standardized, at least as to their traction motors.

From the foregoing, it will be apparent that the apparatus of this invention not only facilitates the act of prying up a brush spring, but additionally locks the spring in elevated position while affording the service man clear and convenient access to the proper brush. Although the apparatus disclosed is of a type for operating upon one spring at any one time, it is to be understood that the apparatus might be adapted for operation upon several springs simultaneously. Although one embodiment has been disclosed in detail, it is to be understood that the invention is not limited thereto, -but the drawings and description thereof are to be understood as being merely illustrative. and variations will present themselves to those skilled in the art without departing from the spirit of this invention or the scope thereof as set forth in the appended claims.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:

l. Apparatus for servicing the commutator brushes in the traction -motors of diesel-electric locomotives, which traction motors have a housing provided with an opening therein affording access to the brushes and brush spring, said apparatus comprising an elongate handle, an open It is to be realized that many modifications head carried at one end of said handle, a bracket ,at the fore part of said head having guide fingers spaced to straddle the brush-spring and disposed to align the head opening over the adjacent brush, and a seat formed adjacent the other end of the handle disposed for seating upon the housing at the edge of the brush-access opening with the brush spring held in elevated condition.l

2. Apparatus for servicing the commutator brushes in the traction motors of diesel-electric locomotives, which traction motors have a housing provided with an opening therein affording access to the brushes and brush springs, and which brush springs swing up from the brushes and away from a tiXed part of said housing, said apparatus comprising an elongate handle, a spring lifter carried at one end of said handle, a seat adjacent the other end of the handle for seating upon the housing, said seat being spaced from said spring lifter a distance corresponding to the distance between said brush spring and said fixed part of the housing when the former is clear of the removal path of its associated brush, and at least one leg projecting from the handle in laterally offset relationship therefrom, said spring lifter being supported on said leg in longitudinally spaced relationship from said handle, thereby to clear the removal path of thc brush, said spring lifter being supported upon a pair of spaced legs extending in laterally offset relationship from the handle, and said spring lifter having guide fingers spaced to straddle the brush spring and disposed to align said spaced legs on opposite sides of the associated brush. 3. Apparatus for servicing the cornmutator brushes in the traction motors of diesel-electric locomotives, which traction motors have a housing provided with an access opening in substantial alignment with but spaced from said brushes, and which brushes are mounted in brush holders and retained therein by a spring-biased member arranged for movement about an axis located on the side of said brush holder remote from said access opening in the housing, said spring-biased member being movable about said axis between brush-retaining and brush-rcicasing positions; said apparatus comprising, an elongate handle, a head extending from one end of the handle, means on said head for engaging said spring-biased member, said means being located on said head in longitudinal alignment with said handle, the portion of said head between said means and said handle being offset laterally from longitudinal alignment with said handle for a distance sufficient to clear a path for the removal of a brush from its brush holder when said means is engaged with said springbiased member in brush-releasing position and said handle extends through said opening, and a seat on said handle spaced from said means a distance corresponding to the distance between an edge `of said opening and said spring-biased member when the latter is in brush-releasing position, said seat being engageable with an edge of said opening to retain said4 spring-biased member in brush-releasing position while said brush is removed from its brush holder through the path cleared by the offset portion of said head.

References Cited in the file of this patent UNITED STATES PATENTS 

